VansAirForceForums  
Home > VansAirForceForums

- POSTING RULES
- Donate yearly (please).
- Advertise in here!

- Today's Posts | Insert Pics


Go Back   VAF Forums > Model Specific > RV-4
Register FAQ Members List Calendar Today's Posts

Reply
 
Thread Tools Search this Thread Display Modes
  #61  
Old 12-16-2015, 06:05 AM
esco esco is offline
 
Join Date: Jan 2011
Location: SoCal
Posts: 391
Default Kudos!

Arlie-

I know this puzzler was frustrating; lots of us were silently watching you work it.

Congrats on sticking to it!
__________________
______
VAF dues paid though exempt
RV-9A sold (I miss that bird!)
RV10 sold (miss that one too!)
RV-14A build underway
Reply With Quote
  #62  
Old 12-16-2015, 12:22 PM
sblack sblack is offline
 
Join Date: Dec 2009
Location: Montreal
Posts: 1,456
Default

Quote:
Originally Posted by acam37 View Post
Today I was sitting in my hangar looking at my ailerons, asking the question "what would cause the aileron to balloon and flex in flight?" And then it dawned on me, The Stiffeners. So I went and took a closer look. What did I find? The stiffeners terminate approx. 3" from the trailing edge, so this could explain a lot. I went ahead and squeezed the trailing edge radius from 3/16" down to 1/8" which tightened the skin a little and straightened it up a bunch. Justin took it up and voila. He said that made a 100% difference in the stick forces. I am still going to build a new set of ailerons, but at least I think I finally solved this mystery.
[IMG][/IMG]
It is amazing and non intuitive how much the trailing edge shape changes the flying qualities. I am sure some airplanes, particularly very small ones like the hummel bird, have been lost because of this.
__________________
Scott Black
Old school simple VFR RV 4, O-320, wood prop, MGL iEfis Lite
VAF dues 2020
Instagram @sblack2154
Reply With Quote
  #63  
Old 12-16-2015, 02:14 PM
swisseagle's Avatar
swisseagle swisseagle is offline
 
Join Date: Feb 2005
Location: 20km outside of Zurich, Switzerland
Posts: 468
Default Buy a set of plans, it is your plane, YOU are responsible for it!

Hello Arlie

Congratulation for you buying an RV-4 and rebuilding them.

It is not the first time here on VAF, that someone bought a plane and having difficulties with it. You found with the help of VAF and your testpilot the root cause.

I just can highly recommend to change all the important parts, so that they exactly are looking like the plans from Vans describe them. It is now your plane, you are responsible for it!

Flying an RV is one part, the community around another ... both are wonderfull! You are at the right place here on VAF!

Btw, there are not so many RV-4 crashes, but those that happend are often loaded to heavy, behind the rear CG limit and doing aerobatics! It is a cross country plane for two, but only a single aerobat machine.

Take care and enjoy!
__________________
Dominik

RV-7A, TMX-IO-320, FM-150, Sensenich FP
Flying since 28. April 2016
Reply With Quote
  #64  
Old 12-16-2015, 02:18 PM
Mike S's Avatar
Mike S Mike S is offline
Senior Curmudgeon
 
Join Date: Sep 2005
Location: Dayton Airpark, NV A34
Posts: 15,420
Default

Quote:
Originally Posted by acam37 View Post
Today I was sitting in my hangar looking at my ailerons, asking the question "what would cause the aileron to balloon and flex in flight?" And then it dawned on me, The Stiffeners. So I went and took a closer look. What did I find? The stiffeners terminate approx. 3" from the trailing edge,
Actually, the rivets terminate at that point, the actual stiffener continues a bit more toward the TE.
__________________
Mike Starkey
VAF 909

Rv-10, N210LM.

Flying as of 12/4/2010

Phase 1 done, 2/4/2011

Sold after 240+ wonderful hours of flight.

"Flying the airplane is more important than radioing your plight to a person on the ground incapable of understanding or doing anything about it."
Reply With Quote
  #65  
Old 12-16-2015, 02:33 PM
Gregg Brightwell's Avatar
Gregg Brightwell Gregg Brightwell is offline
 
Join Date: Jan 2007
Location: Benton, Kansas
Posts: 259
Default Maybe they do, maybe they don't...

Quote:
Originally Posted by Mike S View Post
Actually, the rivets terminate at that point, the actual stiffener continues a bit more toward the TE.
Maybe, maybe not! With the flex that Arlie was describing, I bet they don't go as far back as they SHOULD.

I looked at mine, the last rivet is about an inch from the TE. The stiffener goes back another .75" IIRC.
__________________
Gregg J. Brightwell
Benton, KS
CFII/MEII, ATP, AGI, A&P
-4 Emp and Wings complete!
Fuselage out of the jig!
www.mykitlog.com/gbrightwell
Reply With Quote
  #66  
Old 12-16-2015, 02:35 PM
acam37's Avatar
acam37 acam37 is offline
 
Join Date: Aug 2012
Location: Lufkin Tx
Posts: 689
Default

Quote:
Actually, the rivets terminate at that point, the actual stiffener continues a bit more toward the TE.
Mike, I don't think so in this case. As I described earlier, you can actually manipulate the entire trailing edge by hand. Even where the stiffeners are "supposed to be" in either case, it ain't right. I just don't know why I didn't notice this earlier?
__________________
Arlie Conner (A&P)
RV-4 (N124TT) Sold
RV-8 (N269CP) Sold
RV-4 (N684ML) completed 3-17-19
KOCH Nacogdoches
Reply With Quote
  #67  
Old 12-16-2015, 02:45 PM
Mike S's Avatar
Mike S Mike S is offline
Senior Curmudgeon
 
Join Date: Sep 2005
Location: Dayton Airpark, NV A34
Posts: 15,420
Default

Quote:
Originally Posted by Gregg Brightwell View Post
Maybe, maybe not! With the flex that Arlie was describing, I bet they don't go as far back as they SHOULD.
Gregg------I have no idea how far the stiffeners are designed to go, (notice I used the term "a bit" -----carefully chosen word to give me wiggle room ) I was just pointing out that the end of the stiffener and the location of the rivet are not necessarily relative.

Gonna take x-ray vision or a can opener to tell for sure.
__________________
Mike Starkey
VAF 909

Rv-10, N210LM.

Flying as of 12/4/2010

Phase 1 done, 2/4/2011

Sold after 240+ wonderful hours of flight.

"Flying the airplane is more important than radioing your plight to a person on the ground incapable of understanding or doing anything about it."
Reply With Quote
  #68  
Old 12-16-2015, 06:26 PM
1001001's Avatar
1001001 1001001 is offline
 
Join Date: Dec 2014
Location: Just Minutes from KBVI!
Posts: 1,039
Default

Quote:
Originally Posted by Mike S View Post

Gonna take x-ray vision or a can opener to tell for sure.
Not necessarily...

It may be possible to do it a different way. If you can find a chest or walk-in freezer big enough, freeze the aileron. Then take it out and apply a warm rag a couple inches away from the stiffener on both sides (but don't cover it) just enough to warm the skin. Then breathe on the area. You may be able to see the outline of the stiffener where frost forms from your breath due to the larger thermal mass of the stiffener holding a lower temperature for longer than the thin skin.

Just a thought.
Reply With Quote
  #69  
Old 12-16-2015, 07:07 PM
rvbuilder2002's Avatar
rvbuilder2002 rvbuilder2002 is offline
 
Join Date: Jul 2005
Location: Hubbard Oregon
Posts: 9,035
Default

It doesn't really matter how long the stiffeners are
if there is no rivet near the aft end.
The stiffener effectively ends at the last rivet.
__________________
Opinions, information and comments are my own unless stated otherwise. They do not necessarily represent the direction/opinions of my employer.

Scott McDaniels
Van's Aircraft Engineering Prototype Shop Manager
Hubbard, Oregon
RV-6A (aka "Junkyard Special ")
Reply With Quote
  #70  
Old 12-16-2015, 07:07 PM
CATPart CATPart is offline
 
Join Date: Jan 2012
Location: up up and away
Posts: 312
Default

made me wonder so I just looked at my rv4 plans

Reply With Quote
Reply



Posting Rules
You may not post new threads
You may not post replies
You may not post attachments
You may not edit your posts

vB code is On
Smilies are On
[IMG] code is On
HTML code is Off
Forum Jump


All times are GMT -6. The time now is 06:35 AM.


The VAFForums come to you courtesy Delta Romeo, LLC. By viewing and participating in them you agree to build your plane using standardized methods and practices and to fly it safely and in accordance with the laws governing the country you are located in.